Endoscope with focusing mechanism

Abstract

An endoscope includes a focusing mechanism having a focus control element at a proximal end of the endoscope and a mechanical coupling connecting the focus control element to an image transmitting device (e.g., an electro-optical sensor or one or more optical fibres) mounted at a distal end of an elongated insertion section of the endoscope. Rotation of the focus control element moves the image transmitting device with respect to a lens assembly of the endoscope to focus the image received by the lens assembly. The focus control element may be disengaged from the mechanical coupling by pulling it axially along the length of the insertion section whereby the focusing mechanism may be easily disassembled.

What is claimed is: 
     
       1. An endoscope apparatus for internal inspection of an object, comprising an insertion section elongated along a longitudinal axis between distal end to be inserted into said object and a proximal end to be manipulated by a user,   said distal end enclosing a chamber,   a lens assembly disposed in said chamber,   an electro-optical sensor mounted in said chamber proximally of said lens assembly said sensor being movable along the longitudinal axis, and   a focusing mechanism having a rotatable manipulator at said proximal end and a mechanical coupling connecting said rotatable manipulator to said sensor for causing said sensor to move along the longitudinal axis for focusing in response to rotation of said rotatable manipulator,   said rotatable manipulator having a surface transverse to the longitudinal axis, said transverse surface being disposed in opposing face-to-face engagement with a transverse surface of said mechanical coupling, said rotatable manipulator being connected to said mechanical coupling at said transverse surfaces by a coupling oriented generally parallel to the longitudinal axis so that said manipulator can be disconnected from said mechanical coupling by moving said rotatable manipulator axially away from said mechanical coupling along said longitudinal axis.   
     
     
       2. The apparatus of claim 1 wherein said mechanical coupling comprises a rigid actuator coupled between said rotatable manipulator and said sensor, said actuator moving along the longitudinal axis in response to rotation of said rotatable manipulator.   
     
     
       3. The apparatus of claim 2 wherein said mechanical coupling further comprises a helical surface, and   said rigid actuator includes a follower configured to engage said helical surface and to move along said helical surface in response to rotation of said rotatable manipulator.   
     
     
       4. The apparatus of claim 3 wherein said helical surface is disposed on a member connected to said rotatable manipulator by said coupling. 
     
     
       5. The apparatus of claim 3 wherein said follower comprises a projection on said rigid actuator,   said helical surface comprises a groove on said rotatable manipulator, said follower riding within said groove, and   said mechanical coupling further comprises a slot provided along a portion of the length of said insertion section, said follower riding within said slot.     
     
     
       6. The apparatus of claim 5 wherein said slot is disposed parallel to said longitudinal axis, engagement of said follower and said slot avoiding rotation of said electro-optical sensor during said focusing. 
     
     
       7. The apparatus of claim 2 wherein said rotatable manipulator comprises a sleeve surrounding and rotatable around an external wall of said proximal end. 
     
     
       8. The apparatus of claim 2 wherein said manipulator is rotatable around an external wall of said proximal end and includes an element that is ferromagnetically coupled to said rigid actuator through said wall. 
     
     
       9. The endoscope apparatus of claim 1 further comprising an optical fiber for carrying light along the length of said insertion section to an illumination outlet at said distal end.   
     
     
       10. The endoscope apparatus of claim 9 further comprising an electrical cable for carrying electrical signals from said sensor along the length of said insertion section to said proximal end, and   a flexible conduit connecting said proximal end to a control unit, said electrical cable and said optical fiber carried within said flexible conduit.   
     
     
       11. The endoscope apparatus of claim 10 wherein said flexible conduit has a central axis collinear with said longitudinal axis. 
     
     
       12. An endoscope apparatus for internal inspection of an object, comprising an insertion section elongated along a longitudinal axis between a distal end to be inserted into said object and a proximal end to be manipulated by a user,   said distal end enclosing a chamber,   a lens assembly disposed in said chamber,   an electro-optical sensor mounted in said chamber proximally of said lens assembly, said sensor being movable along the longitudinal axis,   a focusing mechanism having a focus control element at said proximal end and a mechanical coupling connecting said focus control element to said sensor for causing said sensor to move along said longitudinal axis for focusing in response to activation of said focus control element,   said focus control element including a manipulator that is accessible to and rotatable by said user to provide said activation, said manipulator including an outer sleeve having a surface transverse to said longitudinal axis,   said mechanical coupling comprising a helical surface disposed on an inner sleeve which surrounds and is rotatable around said proximal end, said outer sleeve surrounding said inner sleeve with said transverse surface of said outer sleeve being disposed in opposing, face-to-face engagement with a transverse surface of said inner sleeve, said inner sleeve and said outer sleeve being connected at said transverse surfaces by a coupling oriented generally parallel to said longitudinal axis so that said outer sleeve can be disconnected from said inner sleeve by moving said outer sleeve axially away from said inner sleeve along the longitudinal axis, and   a rigid actuator including a follower configured to engage said helical surface and to move along said helical surface in response to rotation of said rotatable manipulator, thereby to cause said rigid actuator to move along the longitudinal axis and move said sensor with respect to said lens assembly.     
     
     
       13. The apparatus of claim 12 wherein said coupling includes a pin for joining said inner and outer sleeves. 
     
     
       14. An endoscope apparatus for internal inspection of a object, comprising an insertion section elongated along a longitudinal axis between a distal end to be inserted into said object and a proximal end to be manipulated by a user,   said distal end enclosing a chamber,   a lens assembly disposed in a chamber in said distal end,   an electro-optical sensor mounted in said chamber proximally of said lens assembly, said sensor being movable along said longitudinal axis, and   a focusing mechanism having   a rotatable focus manipulator at said proximal end, having a surface transverse to said longitudinal axis and   a mechanical coupling having a transverse surface disposed in opposing face-to-face engagement with said transverse surface of said manipulator, said manipulator being connected to said mechanical coupling at said transverse surfaces by a coupling oriented generally parallel to the longitudinal axis so that said manipulator can be disconnected from said mechanical coupling by moving said manipulator axially away from said mechanical coupling along said longitudinal axis, said mechanical coupling having a helical surface disposed on a member connected to said manipulator by a coupling, and   a rigid actuator having a follower configured to engage and move along said helical surface and to cause said actuator to move along said longitudinal axis in response to rotation of said manipulator.     
     
     
       15. An endoscope apparatus for internal inspection of an object, comprising an insertion section elongated along a longitudinal axis between a distal end to be inserted into said object and a proximal end to be manipulated by a user,   a lens assembly disposed in a chamber in said distal end,   an image transmitting device mounted in said chamber of said distal end, said image transmitting device being movable along said longitudinal axis, and   a focusing mechanism having a rotatable manipulator at said proximal end and a mechanical coupling connecting said rotatable manipulator to said image transmitting device for causing said image transmitting device to move along said longitudinal axis with respect to said lens assembly for focusing in response to rotation of said rotatable manipulator,   said rotatable manipulator having a surface transverse to the longitudinal axis, said transverse surface being disposed in opposing face-to-face engagement with a transverse surface of said mechanical coupling, said rotatable manipulator being connected to said mechanical coupling at said transverse surfaces by a coupling oriented generally parallel to the longitudinal axis so that said manipulator can be disconnected from said mechanical coupling by moving said rotatable manipulator axially away from said mechanical coupling along said longitudinal axis.   
     
     
       16. The apparatus of claim 15 wherein said image transmitting device includes an electro-optical sensor for converting said image into an electrical signal.